Stabilization of epinephrine formulations

ABSTRACT

The disclosure herein relates to the innovative epinephrine formulations in aqueous solution of medicinal products that enhance the physicochemical stabilities of epinephrine and extend the product shelf life. In some instances, the formulations comprise epinephrine or a salt thereof, a complexing agent, and a “non-sulfite” antioxidant. The epinephrine formulations substantially demonstrated the superior physicochemical stabilities to conventional sulfite formulation of commercial medications currently available. In some instances, sulfite-free formulations further provide further benefit (e.g., safety benefits) to sulfite-sensitive patients. The compositions, methods for preparing the formulations, and methods of using the same (e.g., in the treatment of anaphylaxis) are also provided.

CROSS-REFERENCE

This application claims the benefit of U.S. Provisional Application Nos.62/351,462 filed on 17 Jun. 2016, and 62/476,852 filed on 26 Mar. 2017,both entitled “Stabilization of Epinephrine Formulations,” and each ofwhich are incorporated herein by reference in their entireties.

FIELD OF THE INVENTION

The invention generally relates to epinephrine formulations,particularly the physicochemical stability enhancement of epinephrineformulations (e.g., injection formulations (1:1000) in aqueous solution,such as for anaphylaxis treatment of anaphylactic shock).

BACKGROUND OF THE INVENTION

Epinephrine, more commonly known as adrenaline, is a hormone secreted bythe medulla of the adrenal glands. Strong emotions such as fear or angercause epinephrine to be released into the bloodstream, which causes anincrease in heart rate, muscle strength, blood pressure, and sugarmetabolism. This reaction, known as the “Flight or Fight Response”,prepares the body for strenuous activity. Epinephrine is found in smallamounts in the body and is essential for maintaining cardiovascularhomeostasis because of its ability to divert blood to tissues understress.

In medicine, epinephrine is used mainly as a stimulant in cardiacarrest, as a vasoconstrictor in shock, and as a bronchodilator andantispasmodic in bronchial asthma. Its uses also include, e.g.,combating low blood pressure during hemorrhagic, allergic oranaphylactic shock; opening the airways during thematic attack;restricting the distribution of locally administered drugs such as localanesthetics; reducing nasal congestion; reducing the amount of fluid inthe eye to decrease intraocular pressure and/or as a performance aid inemergency situations.

Allergic emergencies, such as anaphylaxis, are a growing concern, giventhe increasing awareness of members of the public of their frequency andpotential severity. Anaphylaxis is a sudden, severe, systemic allergicreaction that can be fatal, in many cases, if left untreated.Anaphylaxis can involve various areas of the body, such as the skin,respiratory tract, gastrointestinal tract, and cardiovascular system.Acute symptoms occur from within minutes to two hours after contact withthe allergy-causing substance, but in rare instances onset may bedelayed by as much as four hours. Contact with anaphylaxis-inducingagents, and the severity of the resulting anaphylactic reaction, can beextremely unpredictable. Accordingly, allergists recommend that personswho have a personal or family history of anaphylaxis be prepared toself-administer emergency treatment at all times. Additionally, adultscharged with caring for children who are at risk for anaphylaxis shouldalso be prepared to administer anti-anaphylactic first aid.

The symptoms of anaphylaxis include one or more of the following,generally within 1 to about 15 minutes of exposure to the antigen:agitation, a feeling of uneasiness, flushing, palpitations,paresthesias, pruritus, throbbing in the ears, coughing, sneezing,urticaria, angioedema, difficulty breathing due to laryngeal edema orbronchospasm, nausea, vomiting, abdominal pain, diarrhea, shock,convulsions, incontinence, unresponsiveness and death. An anaphylacticreaction may include cardiovascular collapse, even in the absence ofrespiratory symptoms.

Due to its vasoconstrictive effects, epinephrine is the drug of choicefor treating anaphylaxis. Allergy patients undergoing immunotherapy mayreceive an adrenaline rinse before the allergen extract is administered,thus reducing the immune response to the administered allergen.

Epinephrine in aqueous solution deteriorates rapidly on exposure to airor light or heat and discolors to pink from the oxidation toadrenochrome and to brown from the formation of melanin.

Epinephrine is a catechol compound that is sensitive to oxidation too-quinones, which can react further to form highly colored compounds.Epinephrine can thus react to form adrenochrome, a highly colored indolederivative. The rate of this reaction increases with pH, temperature andby the presence of metal ions, such as aluminum from various rubbers andiron from amber glassware. Epinephrine solutions may also lose potencyas a result of racemization, and protection from light minimizes thisform of instability.

The modification or degradation of the catechol amines is undesirablefor a number of reasons. Modification of the catechol amine results inloss of titer of the active ingredient, formation of compounds which mayhave undesirable physiological effects, and the appearance of a darkcolor, which makes the solution offensive and unmarketable. The initialloss of active compound due to auto-oxidation during the preparation andpackaging of such a solution is substantial despite the fact that suchprocedures are carried out as nearly as practically possible in an inertatmosphere. Such a solution must be stored under refrigeration in orderto decrease the rate of deterioration of the compound and thus prolongits shelf-life.

It is a standard practice, in order to stabilize adrenergic compoundssuch as catechol amines against auto-oxidation, to combine the same withan antioxidant. Various antioxidants which have been used to stabilizecatechol amine solution in a variety of formulations such as aerosols,eye-drops, injections etc. including metabisulfite, bisulfite, sulfite,ascorbic acid, thioglycollate, thioglycerol, cysteine, propyl gallateand formaldehyde sulfoxylate (References: GB 425678, GB 930452, U.S.Pat. Nos. 3,149,035, 3,966,905, CA 981182, US 2008/0269347 A1, DD-A1-150694, WO 94/13274, WO 97/16196, WO98/20869, U.S. Pat. No. 4,734,438).

For anaphylactic treatment, the usual epinephrine concentration is0.3-0.5 mg in 1:1000 dilution for subcutaneous or intramuscularinjection, which is commercially available in auto injector devices suchas EpiPen®, Twinject®, Adrenaclick® and Auvi-Q™. For instance accordingto its prescribing information, EpiPen® is designed to deliver a minimumof 0.3 mg epinephrine in a 0.3 mL injection volume. Its composition in 1mL water for injection consists of either 1.0 mg epinephrine as freebase, 6.0 mg sodium chloride, 1.7 mg sodium metabisulfite andhydrochloric acid to adjust pH 2.2-5.0. Twinject® and Adrenaclick® has acomparable composition to Epipen®, but instead uses sodium bisulfite asan antioxidant and includes chlorobutanol as a preservative. Auvi-Q™ hasa comparable composition to Twinject® and Adrenaclick® in an absence ofchlorobutanol.

Note that a sulfite related compound i.e. sodium metabisulfite or sodiumbisulfite, which is commonly used in the conventional epinephrineformulations as an antioxidant, has been associated with some othersevere allergic reactions (EpiPen® Prescribing Information 2014; Auvi-Q™Prescribing Information 2014; Adrenaclick® Prescribing Information 2013;The Australasian Society of Clinical Immunology and Allergy (ASCIA),Sulfite Sensitivity, 2014; Papaioannou R. and Pfeiffer C. C., SulfiteSensitivity, Journal of Orthomolecular Psychiatry, 13(2), 105-110,1984). In addition, sodium bisulfite can directly react with epinephrineto rapidly reduce its potency and produce a degradation product,epinephrine sulfonic acid (ESA). The increase of ESA in the epinephrineformulation containing a sulfite related compound could be greater than15% at the end of product life (about 12-18 months). The safety and/ortoxicity of ESA in commercial epinephrine products for anaphylactictreatment are still not well understood. In addition, the potency ofepinephrine also could be substantially degraded due to such reaction tonearly 20% at the end of product life.

Therefore all commercial products on the market must overage about10-12% epinephrine during the manufacturing process in order tocompensate a fast decay of its potency. This means that any patient whoreceived epinephrine injection at the beginning versus the end ofproduct life might have 20% dose variation during an emergencytreatment. The actual shelf lives of all commercial products would beshortened if they are exposed to a higher temperature than a roomtemperature i.e. 25° C. for a period of time. In addition, allcommercial products must have clear windows on the injection devicese.g. auto injectors to observe the product discolorations and warningsof the product exposures to excursion temperatures on the labels.

Thermally induced epinephrine degradation in an aqueous solution is notonly the oxidation process but also the racemization one as well. Anactive drug isomer, l-epinephrine can be rearranged to produce a littleor no pharmacological isomer of d-epinephrine. The epinephrineracemization in commercial formulations was reported to be ˜10% d-isomerafter ˜4 year storage at pH 2.4 or after ˜3 year at pH 3.0-3.5(Stepensky D., Chorny M., Dabour Z. and Schumacher I., Long-TermStability Study of L-Adrenaline Injections: Kinetics of Sulfonation andRacemization Pathways of Drug Degradation; Journal of PharmaceuticalSciences., 93(4), 969-980, 2004). A commercially approved product,Adrenalin® 1 mL and 30 mL have a limitation of ≤9.5% d-epinephrinecontent at the end of shelf lives for 18 and 14 months, respectively(U.S. Pat. No. 9,119,876 B1).

This Background is provided to introduce a brief context for the Summaryand Detailed Description that follow. This Background is not intended tobe an aid in determining the scope of the claimed subject matter nor beviewed as limiting the claimed subject matter to implementations thatsolve any or all of the disadvantages or problems presented above.

SUMMARY OF THE INVENTION

Provided in certain embodiments herein are epinephrine compositions(e.g., aqueous formulations), such as that have good physicochemicalstability. In some instances, the compositions provided herein provideexcellent physicochemical stability, while using very small amounts ofantioxidants, complexing agents, and/or other additives. In certaininstances, compositions provided herein surprisingly demonstrate greatlyimproved physicochemical stability by greatly reducing the amounts ofadditives included. In specific embodiments, compositions providedherein have good potency retention, good visual characteristics (i.e.,colorlessness), and low formation of degradation products, even atrigorous storage conditions.

Also provided herein are compositions and methods for the treatment ofanaphylaxis (or any of the symptoms associated therewith, such asdescribed herein), anaphylactic shock, or the like. In anotherembodiment, provided herein are compositions and methods for treatingcardiac arrest, bronchial asthma, croup, nasal congestion, reducingfluid in the eye, decreasing intraocular pressure, and/or treatingglaucoma.

In specific embodiments, compositions provided herein are aqueousformulations. In some instances, also provided herein are methods forenhancing the physicochemical stability of epinephrine in aqueoussolution, such as by formulating epinephrine in accordance with thedisclosures herein. In specific embodiments, formulation of compositionsherein comprises utilization of epinephrine with a complexing agent,such as a native or modified cyclodextrin derivative to provide aninclusion complex with epinephrine((−)-3,4-Dihydroxy-α-[methylamino)methyl]benzyl alcohol). In further oralternative embodiments, formulation of compositions herein comprisesutilization of epinephrine with an antioxidant, such as cysteine, or acombination of antioxidants. Surprisingly, it is found and illustratedin certain embodiments herein that very low relative amounts ofantioxidant are preferred in order to provide good physicochemicalstability. Formulation of such compositions optionally comprisesadditional agents, such as described herein in the amounts describedherein. In certain embodiments, epinephrine and other agents included inthe composition are combined into the formulation in either neutral(e.g., free base or acid) or salt form, such as discussed in more detailherein. In a specific embodiment, provided herein is a method ofpreparing a pharmaceutical composition (e.g., aqueous solution)comprising combining epinephrine or a pharmaceutically acceptable saltthereof, with one or more antioxidant (such as described herein) or apharmaceutically acceptable salt thereof, a pH buffering agent or apharmaceutically acceptable salt thereof, a chelating agent or apharmaceutically acceptable salt thereof, and a tonicity modifier intoan aqueous medium. In more specific embodiments, the process furthercomprises combining a complexing agent or a pharmaceutically acceptablesalt thereof therewith. In certain instances, compositions describedherein as comprising an agent optionally comprise the agent asdescribed, an ion (e.g., pharmaceutically acceptable ion) thereof, asalt (e.g., pharmaceutically acceptable salt) thereof, or a solvate(e.g., hydrate) thereof, or the like, as applicable.

In certain embodiments, provided herein is epinephrine and one or moreantioxidant. In some instances, at very low concentrations ofantioxidant, rapid degradation of epinephrine is observed. In additionalinstances, at higher concentrations of antioxidant, undesirabledegradation of epinephrine occurs over time. In certain embodimentsherein, antioxidant is provided in an amount to provide good stabilityof epinephrine initially, and over time, such as described in moredetail herein. In some embodiments, the antioxidant is cysteine,acetylcysteine, thioglycerol, or any combination thereof. In variousembodiments, other antioxidants, such as described herein are used inaddition to and/or instead of such antioxidants. In certain embodiments,antioxidants are provided in the composition in a (e.g., combined ortotal) amount as described herein, such as about 0.005 wt. % to lessthan 0.1 wt. %. In specific embodiments, antioxidant is present in anamount of about 0.005 wt. % to about 0.07 wt. %. In more specificembodiments, antioxidant is present in an amount of about 0.005 wt. % toabout 0.05 wt. %. In still more specific embodiments, antioxidant ispresent in an amount of about 0.005 wt. % to about 0.035 wt. %. In yetmore specific embodiments, antioxidant is present in an amount of about0.005 wt. % to about 0.03 wt. %. In some embodiments, antioxidant ispresent in an amount of about 0.01 wt. % to less than 0.1 wt. %. Inspecific embodiments, antioxidant is present in an amount of about 0.01wt. % to about 0.07 wt. %. In specific embodiments, antioxidant ispresent in an amount of about 0.01 wt. % to about 0.07 wt. %. In morespecific embodiments, antioxidant is present in an amount of about 0.01wt. % to about 0.05 wt. %. In still more specific embodiments,antioxidant is present in an amount of about 0.01 wt. % to about 0.035wt. %. In yet more specific embodiments, antioxidant is present in anamount of about 0.01 wt. % to about 0.03 wt. %. In further embodiments,the composition further comprises antioxidant, a pH buffering agent, achelating agent, and a tonicity modifier. In yet further embodiments, acomposition provided herein further comprises a complexing agent (e.g.,cyclodextrin).

In one embodiment, a composition provided herein comprises epinephrine,complexing agent, antioxidant, pH buffering agent, chelating agent andtonicity modifier in an aqueous based media. In some embodiments, aprovided herein comprises epinephrine, antioxidant, pH buffering agent,chelating agent and tonicity modifier in an aqueous based media.

In specific embodiments, provided herein is a pharmaceutical compositioncomprising:

-   -   a. epinephrine;    -   b. complexing agent (e.g., a cyclodextrin) (e.g., in a molar        ratio of complexing agent-to-epinephrine of about 1:10 to about        10:1);    -   c. antioxidant (e.g., cysteine) (e.g., in an amount of less than        0.1 wt. %, about 0.01 wt % to about 0.07 wt. %, about 0.01 wt. %        to about 0.05 wt. %, or the like);    -   d. pH buffering agent;    -   e. chelating agent;    -   f. tonicity modifier; and    -   g. an aqueous medium.

In certain embodiments, a composition provided herein has goodphysicochemical stability. In some embodiments, after six months ofstorage at 40° C. and 75% relative humidity (RH), the compositioncomprises at least 90 wt. % (e.g., at least 95 wt. %) of the epinephrinein the composition prior to storage. In further or alternativeembodiments, after six months of storage at 40° C. and 75% relativehumidity (RH), the composition comprises less than 10 wt. % (e.g., lessthan 5 wt. %) epinephrine degradant. In certain embodiments, acomposition provided herein has a shelf life (e.g., retaining at least90 wt. % (e.g., at least 95 wt. %) initial epinephrine) (e.g., atconditions of about 25° C., such as at 60% RH) of at least 2 years, suchas at least 2.5 years, or at least 3 years. In some embodiments, afterstorage (e.g., after 3.5 months or six months of storage at 40° C. and75% relative humidity (RH)), less than 10 wt. % of the epinephrine in acomposition provided herein is d-epinephrine. In specific embodiments,less than 9.5 wt. %, less than 6 wt. %, less than 5 wt. %, or less than3 wt. % of the epinephrine in a composition provided herein isd-epinephrine after storage (e.g., after storage for at least 1 year, 2years, or 3 years at conditions of about 25° C., such as at 60% RH, orfor at least 3.5 months or 6 months at 40° C. and 75% RH). In certaininstances, such temperatures are generally kept within ±2° C. and suchrelative humidities are generally kept within ±5%. In certainembodiments, a composition provided herein after 12 months of storage at25±2° C. and 60±5% relative humidity (RH), (i) the composition comprisesat least 90 wt. % (e.g., at least 95 wt. %, at least 97 wt. %, at least98 wt. %, or the like) of the epinephrine in the composition prior tostorage; and/or (ii) the composition is substantially colorless

In addition to retaining good potency over extended periods of time,compositions provided in certain embodiments herein also possess goodvisual characteristics and minimal formation of degradation products aswell. In some embodiments, the compositions provided hereinsubstantially retain their colorless nature, even after long and/orrigorous storage conditions. In specific embodiments, the compositionsprovided herein remain substantially colorless (e.g., colorless to thenaked eye) after storage for at least 2 years, at least 3 years or thelike (such as at about 25° C., e.g., at 60% RH). In further oralternative embodiments, compositions provided herein remainsubstantially colorless (e.g., colorless to the naked eye) after (e.g.,six months) of storage at 40° C./75% RH. In certain embodiments, afterstorage for at least 2 years, at least 3 years or the like (such as atabout 25° C., e.g., at 60% RH) a composition provided herein (e.g.,comprising about 0.1 wt. % epinephrine) has an optical density (O.D.)(e.g., absorbance at a maximum wavelength or max at 485 nm) of less than0.1, e.g., less than 0.05, less than 0.02, less than 0.01, or the like.In further or alternative embodiments, after storage for at least 6months (such as at about 40° C., e.g., at 75% RH) a composition providedherein (e.g., comprising about 0.1 wt. % epinephrine) has an opticaldensity (O.D.) (absorbance at a maximum wavelength or λmax at 485 nm) ofless than 0.1, e.g., less than 0.05, less than 0.02, less than 0.01, orthe like.

In certain embodiments, compositions provided herein compriseepinephrine in an amount suitable for therapeutic benefit. In specificembodiments, the composition comprises about 0.0001 wt. % to about 1 wt.% (e.g., about 0.001 wt. % to about 1 wt. %, or about 0.01 wt. % toabout 1 wt. %), or more, epinephrine. In more specific embodiments, suchas in (1:1000) formulations (e.g., which are optionally utilized in thetreatment of anaphylactic shock, anaphylaxis, or the like), compositionsprovided herein comprise about 0.05 wt. % to about 0.15 wt. %, such asabout 0.1 wt. % epinephrine. In specific embodiments, a compositionprovided herein comprises about 0.05 wt. % or about 0.5 mg/mL ofepinephrine (e.g., on a free base weight basis), such as a formulation(1:2000) for certain pediatric uses. In other specific embodiments, acomposition provided herein comprises about 0.1 wt. % or about 1 mg/mLof epinephrine (e.g., on a free base weight basis), such as aformulation (1:1000) for certain adult uses. In some embodiments,epinephrine is formulated into a composition herein as a free base or asa pharmaceutically acceptable salt thereof, such as described herein.

In certain embodiments, a composition provided herein comprises acyclodextrin (e.g., as a complexing agent thereof). In specificembodiments, the cyclodextrin is sulfobutylether ß-cyclodextrin (SBEßCD)or hydroxypropyl ß-cyclodextrin (HPßCD). In some embodiments, thecyclodextrin is present in the composition in acyclodextrin-to-epinephrine molar ratio of about 1:10 to about 10:1,e.g., about 1:3 to about 2:1 (e.g., about 1:2.5 to about 1:1.5). Infurther or alternative embodiments, the composition comprises about0.001 wt. % to about 10 wt. % (e.g., about 0.01 wt. % to about 10 wt. %)complexing agent. In other embodiments, a complexing agent, such ascyclodextrin, is omitted from the formulation.

In some embodiments, a composition provided herein comprises a cysteine(e.g., as an antioxidant thereof). In certain embodiments, the cysteineis present in the composition in a weight ratio ofcysteine-to-epinephrine of about 1:2 or less, or about 1:5 or less(e.g., down to about 1:50, or about 1:20). In specific embodiments, thecysteine is present in the composition in a weight ratio ofcysteine-to-epinephrine of about 1:10. In further or alternativeembodiments, the composition comprises to be less than 0.05 wt. %cysteine, such as about 0.03 wt. % or less, or about 0.02 wt. % or less.In certain embodiments, the composition comprises about 0.001 wt. %cysteine or more (e.g., about 0.001 wt. % to about 0.05 wt. %), such asabout 0.005 wt. % or more (e.g., 0.005 wt. % to about 0.05 wt. %).

In certain embodiments, a composition provided herein comprises citrateand/or citric acid (e.g., as a buffering agent thereof) (e.g., therelative concentration and presence of citrate and/or citric acidpresent in an aqueous composition depending on the pH of thereof). Incertain embodiments, the composition comprises about 0.01 wt. % or lessof citric acid and citrate combined (e.g., about 0.001 wt. % to about0.01 wt. %).

In some embodiments, the pH of a composition provided herein is about 2to about 5 (e.g., about 2 to about 4). In specific embodiments, the pHof the composition is about 2.5 to about 3.5.

In certain embodiments, a composition provided herein comprises edetate(e.g., as a chelating agent). In some embodiments, the compositioncomprises about 0.01 wt. % of edetate or less (e.g., about 0.001 wt. %to about 0.01 wt. %).

In some embodiments, a composition provided herein has an osmolality inthe range of about 200 mOsm/kg to about 400 mOsm/kg. In certainembodiments, a tonicity modifier is present in the composition in anamount suitable to provide a solution osmolality in the range of about200 mOsm/kg to about 400 mOsm/kg. In some embodiments, a compositionprovided herein is formulated with a salt, such as sodium chloride, as atonicity modifier, which would be dissolved at least partially dissolvedin an aqueous medium. In some embodiments, a composition provided hereincomprises about 0.01 wt. % to about 5 wt. % (e.g., about 0.1 wt. % toabout 1 wt. %) of a tonicity modifier (e.g., dissolved sodium chloride).

In specific embodiments, provided herein is a pharmaceutical compositioncomprising:

-   -   a. epinephrine;    -   b. complexing agent (e.g., cyclodextrin) (e.g., in a molar ratio        of complexing agent-to-epinephrine of about 1:10 to about 10:1);    -   c. antioxidant (e.g., cysteine, acetylcysteine, thioglycerol, or        any combination thereof) (e.g., in a (combined) amount of less        than 0.1 wt. %, such as about 0.07 wt. % or less, about 0.05 wt.        % or less, about 0.035 wt. % or less, or about 0.03 wt. % or        less, e.g., down to about 0.01 wt. % or down to about 0.005 wt.        %);    -   d. a pH buffering agent;    -   e. a chelating agent;    -   f. a tonicity modifier; and    -   g. an aqueous medium.

In some embodiments, provided herein is a pharmaceutical compositioncomprising:

-   -   a. epinephrine;    -   b. antioxidant (e.g., cysteine, acetylcysteine, thioglycerol, or        any combination thereof) (e.g., in a (combined) amount of less        than 0.1 wt. %, such as about 0.07 wt. % or less, about 0.05 wt.        % or less, about 0.035 wt. % or less, or about 0.03 wt. % or        less, e.g., down to about 0.01 wt. % or down to about 0.005 wt.        %);    -   c. pH buffering agent;    -   d. chelating agent;    -   e. tonicity modifier; and    -   f. an aqueous medium.

In specific embodiments, provided herein is a pharmaceutical compositioncomprising:

-   -   a. epinephrine;    -   b. cysteine (e.g., in an amount of less than 0.1 wt. %, such as        about 0.07 wt. % or less, about 0.05 wt. % or less, about 0.035        wt. % or less, or about 0.03 wt. % or less, e.g., down to about        0.01 wt. % or down to about 0.005 wt. %);    -   c. a pH buffering agent;    -   d. a chelating agent;    -   e. a tonicity modifier; and    -   f. an aqueous medium.

In various embodiments, specific details of any of such compositions aresuch as described above and herein.

In specific embodiments, pharmaceutical compositions provided herein areformulated for injection. In such embodiments, the aqueous mediumutilized is water suitable for injection (WFI). In specific embodiments,such water is sterile. In some embodiments, the composition is loadedinto an administrative device, such as a device for administering thecomposition to an individual via injection. In specific embodiments, theadministrative device is a syringe or a cartridge suitable for use in amanual and/or auto injector (e.g., that can precisely and accuratelydeliver effective amount of epinephrine medication).

Provided in various embodiments herein are compositions comprising (orformulated with) epinephrine (e.g., formulated as a free base) as anactive pharmaceutical ingredient and used at a range of about0.0001-1.0% (e.g., based on free base concentration). In someembodiments, the composition comprises a modified ß-cyclodextrin, suchas either hydroxypropyl β-cyclodextrin (HPßCD) or sulfobutyl etherβ-cyclodextrin (SBEßCD) (e.g., as a complexing agent), in a molar ratioof cyclodextrin-to-epinephrine of about 1:10 to about 10:1 (e.g., about1:3 to about 2:1). Within further or additional embodiments, thecomposition comprises (or is formulated with) cysteine (L-cysteine)(e.g., as an antioxidant) at a concentration of about 0.005 wt. % to 0.1wt. %, (e.g., about 0.005 wt. % to about 0.07 wt. %, about 0.005 wt. %to about 0.05 wt. %, about 0.005 wt. % to about 0.035 wt. %, about 0.005wt. % to about 0.03 wt. %, or the like, such as above 0.01 wt. %) or aweight ratio of cysteine-to-epinephrine of about 1:20 to about 1:2(e.g., about 1:20 to about 1:5, about 1:20 to about 1:10, or about1:10). Within certain embodiments, the composition comprises (or isformulated with) citric acid/citrate as a pH buffering agent at aconcentration of about 0.005 wt. % to about 0.05 wt. % or at a weightratio of citric acid-to-epinephrine of about 1:20 to about 1:2 (e.g.,about 1:20 to about 1:5, about 1:20 to about 1:10, or about 1:10). Infurther or alternative embodiments, compositions provided hereincomprise (or is formulated with) edetate (e.g., formulated as edetatedisodium) (e.g., as a chelating agent) at a concentration of about 0.005wt. % to about 0.05 wt. % or a weight ratio of edetate-to-drug of about1:20 to about 1:2 (e.g., about 1:20 to about 1:5, about 1:20 to about1:10, or about 1:10).

In certain embodiments, provided herein is a method of treatinganaphylactic shock, anaphylaxis, or other allergic reaction byadministering a composition provided herein to an individual in needthereof. In specific embodiments, a composition provided herein isadministered by intramuscular injection or subcutaneous injection orintravenous injection, such as with a syringe or a manual and/or autoinjector (such as described herein).

In some embodiments, provided herein are methods of preparing (e.g.,physiochemically stable) pharmaceutical compositions comprisingepinephrine (e.g., for treating anaphylaxis or anaphylaxis shock, suchas by injection), the methods comprising combining in an aqueous medium:

-   -   a. epinephrine, or a pharmaceutically acceptable salt thereof;    -   b. cysteine (e.g., in an amount of less than 0.05 wt. %), or a        pharmaceutically acceptable salt thereof;    -   c. a pH buffering agent (e.g., citric acid, or other agent, such        as described herein);    -   d. a chelating agent (e.g., edetate or a pharmaceutically        acceptable salt thereof); and    -   e. a tonicity modifier (e.g., sodium chloride or dextrose).

In specific embodiments, the agents are optionally combined into asingle aqueous medium, or combined in parts of the aqueous medium priorto combing the parts of the aqueous medium to formulate the finalcomposition. In one specific embodiment, the epinephrine is combinedinto a first aqueous medium part, the remainder cysteine, pH bufferingagent and chelating agent are combined into a second aqueous mediumpart, before the first and second aqueous medium parts are combined. Insome embodiments, a tonicity modifier is added to achieve the desiredosmolality to the first part, the second part, and/or the combinationthereof. In addition, in some embodiments, the method further comprisescombining a complexing agent (e.g., in a molar ratio (complexingagent-to-epinephrine) of about 10:1 to about 1:10, such as describedherein) into the composition, the complexing agent optionally beingadded at any point, such as to the first part, the second part, or thecombination thereof. Other variants are also contemplated by the methodsherein, such as wherein each component is individually dissolved in itsown aqueous medium part prior to combination. In addition, in someinstances, the combined parts are optionally further diluted (e.g., withan aqueous medium having the osmolality in the range of that desired forthe final product, such as about 200 mOsm/kg to about 400 mOsm/kg) toachieve the desired volume and concentration. Exemplary concentrationsand specific types of agents utilized in such methods are as describedherein.

In certain embodiments, provided herein is an aqueous compositioncomprising epinephrine (e.g., as a free base, ion, solvate, salt, etc.thereof) in a concentration (e.g., based on the concentration of thefree base) of about 0.001 mg/mL to about 50 mg/mL, or, e.g., about 0.5mg/mL to about 1.5 mg/mL, or about 1 mg/mL. In some embodiments,provided herein is an aqueous composition comprising a complexing agent(e.g., a cyclodextrin, such as SBEßCD described herein) in aconcentration of about 1.2 mg/mL to about 24 mg/mL, such as about 5mg/mL to about 7 mg/mL or about 6 mg/mL. In some embodiments, providedherein is an aqueous composition comprising a complexing agent (e.g., acyclodextrin, such as HPßCD described herein) in a concentration ofabout 0.8 mg/mL to about 16 mg/mL, such as about 3 mg/mL to about 5mg/mL or about 4 mg/mL. In some embodiments, provided herein is anaqueous composition comprising an antioxidant (e.g., cysteine (e.g., asa free base, ion, solvate, salt, etc. thereof)) in a concentration ofabout 0.5 mg/mL or less, such as about 0.2 mg/mL or less, about 0.001 toabout 0.5 mg/mL, about 0.01 mg/mL to about 0.2 mg/mL, about 0.05 toabout 0.15 mg/mL, or about 0.1 mg/mL. In certain embodiments, providedherein is an aqueous composition comprising a buffering agent (e.g.,citric acid/citrate (e.g., comprising both free acid and conjugate baseforms)) in a concentration of about 5 mg/mL or less, such as about 1mg/mL or less, about 0.5 mg/mL or less, about 0.2 mg/mL or less, about0.001 to about 0.5 mg/mL, about 0.01 mg/mL to about 0.2 mg/mL, about0.05 to about 0.15 mg/mL, or about 0.1 mg/mL. In certain embodiments,provided herein is an aqueous composition comprising a chelating agent(e.g., edetate, such as in a form described herein) in a concentrationof about 5 mg/mL or less, such as about 1 mg/mL or less, about 0.5 mg/mLor less, about 0.2 mg/mL or less, about 0.001 to about 0.5 mg/mL, about0.01 mg/mL to about 0.2 mg/mL, about 0.05 to about 0.15 mg/mL, or about0.1 mg/mL. In certain embodiments, pharmaceutical compositions areprepared utilizing agents in such amounts. In certain embodiments, whilein some instances formulation provided herein are prepared using a salt(e.g., pharmaceutically acceptable salt) of an agent herein(epinephrine), weight percentages are provided using the weightpercentage of the free base of the agent provided, rather than the saltutilized to formulate the composition.

This “Summary of the Invention” or “Summary” section is provided tointroduce a selection of concepts in a simplified form. The concepts arefurther described in the “Detailed Description of the Invention”section. Elements or steps other than those described in this Summaryare possible, and no element or step is necessarily required. ThisSummary is not intended to identify key features or essential featuresof the claimed subject matter, nor is it intended for use as an aid indetermining the scope of the claimed subject matter. The claimed subjectmatter is not limited to implementations that solve any or alldisadvantages noted in any part of this disclosure.

In specific embodiments, compositions and formulations provided hereinare sulfite free, or do not comprise sulfite, such as metabisulfiteand/or bisulfite. In certain embodiments, the amount of sulfite in acomposition provided herein is less than 0.001 wt. % (e.g., less than0.0001 wt. %).

In some embodiments, compositions described herein are formulated forparenteral administration (e.g., intramuscular injection or subcutaneousinjection or intravenous injection), topical administration, sprayadministration (e.g., nasal administration, buccal, or sublingualadministration), pulmonary administration (e.g., by inhalation followingaerosolization or nebulization), ophthalmic administration, oraladministration, or the like. In certain embodiments, provided herein arecompositions suitable for administration via such techniques. In someembodiments, such compositions comprise epinephrine (or apharmaceutically acceptable salt, ion, solvate, or the like thereof) andother optional components (e.g., a complexing agent, such as acyclodextrin, and/or antioxidant, such as a cysteine), such as in theratios and/or weights described herein.

In a specific embodiment, a composition herein formulated intopharmaceutical dosage forms of a solid or gel dosage form, such as afast dissolving composition, e.g., an orally disintegrating ordissolving tablet or other dosage form. In specific embodiments, a soliddosage form optionally comprises a lyophilized formulation (e.g.,lyophilized from an aqueous formulation, such as described herein). Incertain embodiments, such compositions are administered and/or suitablefor buccal and/or sublingual administration via mucosal tissueabsorption in the mouth. In another specific embodiment, a compositionprovided herein is formulated into pharmaceutical dosage forms suitablefor parenteral medication by (re)constituting a lyophilized formulation,such as described herein, into a solution. In certain embodiments, such(re)constituted compositions are then administered by suitable methods,such as via intramuscular injection, subcutaneous injection, orintravenous injection. In some embodiments, a composition providedherein is formulated as a topical medication, such as a solution, patch,cream, ointment, gel or the like. In specific embodiments, suchformulations are suitable for topical administration to (and absorptionby) the skin (e.g., intact or broken skin). In some embodiments, acomposition herein is formulated as a spray medication, such as foradministration via nasal absorption, buccal and/or sublingualabsorptions, and/or topical absorption via the skin (e.g., broken orintact). In certain embodiments, the composition is formulated as aninhalation medication. In specific embodiments, such formulations areadministered by nebulization into aerosol and administrating drug viapulmonary absorption. In some embodiments, a composition herein isformulated as an ophthalmic medication. In specific embodiments, suchformulations are in the form of a solution, cream, ointment, gel or thelike. In some embodiments, such compositions or formulations areadministered for intraocular absorption.

Compositions and formulations described herein are administered by andusing any suitable method and/or device. In specific embodiments, acomposition or formulation provided herein is loaded into anadministrative device that delivers an effective amount of medication.In specific embodiments, the administrative device is, by way ofnon-limiting example, a syringe or a cartridge suitable for deliveringparenteral medications via a manual and/or auto injector, a syringe oran actuator suitable for delivering a spray medication, a nebulizersuitable for delivering an aerosol medication, and an applicator ordropper or container (e.g. bottle or squeezable tube) suitable fordelivering ophthalmic and topical medications.

In some embodiments, provided herein are methods of restricting thedistribution of locally administered drugs such as local anesthetics forparenteral administration or topical administration (e.g., for bothintact and broken skins), such as by using a composition hereinformulating with an anesthetic agent or anesthetic agents. In someembodiments, provided herein is a method of providing anesthesia to anindividual by administering a composition described herein and furthercomprising an anesthetic agent or anesthetic agents (e.g., articaine,bupivacaine, chloroprocaine, cocaine, etidocaine, lidocaine,mepivacaine, prilocaine, procaine, ropivacaine, tetracaine and/or acombination thereof).

In some embodiments, concentrations are described herein. In specificinstances, the concentration refers to the concentration of a compounditself or the free base thereof, with explicit disclosure for both beingcontemplated in each instance. For example, a disclosure referring tothe concentration of an epinephrine salt herein refers to expressdisclosure of the concentration of the salt itself and the concentrationof epinephrine (free base), unless otherwise noted.

In certain disclosures herein, a composition comprising an agent isdescribed. Generally, the disclosure includes disclosure of andreference to the agent itself, salts thereof (e.g., pharmaceuticallyacceptable salts thereof), solvates thereof (e.g., hydrates), ionsthereof, a free base thereof, conjugate acid thereof, and the like. Forexample, disclosure and claims of a composition herein comprisingepinephrine herein includes disclosure of and reference to compositionscomprising epinephrine, salts thereof, free base thereof, ions thereof,solvates thereof, and the like, unless otherwise noted.

In various embodiments herein, compositions and methods provided hereindescribe the use of “a” or “an” agent. Such disclosures includedisclosure of and reference to “one and only one” and “one or more” ofsuch agent(s), unless otherwise noted. In some instances, whereinmultiple agents are utilized, reference to concentrations of “a” or “an”such agent includes reference to the combined concentration of themultiple agents.

In certain embodiments, disclosure of a value herein includes disclosureof a value about equal to that value. In various embodiments, a value is“about” the value if it is between ½ and 2× that value, such as about±50%, ±20%, ±10%, ±5%, or the like. In addition, any disclosure of avalue “about” a specific number includes disclosure of that numberitself. For example, disclosure of a range of about 0.01 wt. % to about0.07 wt. % of epinephrine herein includes disclosure of 0.01 wt. % to0.07 wt. %.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 demonstrated the fraction of epinephrine complex with SBEßCD atpH 3.5 (K=488 M⁻¹) and pH 5.5 (K=111 M⁻¹).

FIG. 2 illustrates an HPLC chromatogram of epinephrine degradation in apresence of 1:1 weight ratio of cysteine-to-drug at pH 2.5 after 1 monthat 50° C.

FIG. 3 illustrates an HPLC chromatogram of epinephrine stability inSBEßCD formulation containing 1:10 weight ratio of cysteine-to-drugafter 1 month at 50° C.

FIG. 4 illustrates an HPLC chromatogram of epinephrine stability inHPßCD formulation containing 1:10 weight ratio of cysteine-to-drug after1 month at 50° C.

FIG. 5 illustrates an HPLC chromatogram of epinephrine stability innon-complex formulation containing 1:10 weight ratio of cysteine-to-drugafter 1 month at 50° C.

FIG. 6 illustrates the HPLC chromatogram of epinephrine stability inSBEßCD formulation after 6 months at 40° C.

FIG. 7 illustrates the HPLC chromatogram of epinephrine stability inHPßCD formulation after 6 months at 40° C.

FIG. 8 illustrates the HPLC chromatogram of epinephrine chirality inSBEßCD formulation after 3.5 months at 40° C.

FIG. 9 illustrates the HPLC chromatogram of epinephrine chirality inHPßCD formulation after 3.5 months at 40° C.

DETAILED DESCRIPTION OF THE INVENTION

In order to prevent the thermal and/or oxidative degradations ofepinephrine, commercial formulations available on the market arecurrently using a common conventional antioxidant of sulfite relatedcompounds such as sodium bisulfite and/or sodium metabisulfite etc. Theexamples of marketed products of epinephrine auto injectors foranaphylaxis treatment include EpiPen®, Twinject®, Adenaclick® andAuvi-Q™. The sulfite related compounds can directly react withepinephrine, resulting in a substantial loss of epinephrine potency andgenerating degradation products, such as epinephrine sulfonic acid(ESA), which rapidly increases with time and becomes a major limitingfactor to the product shelf life.

In some instances, sulfite related compounds in foods and/or medicationscause a severe allergy or asthma reaction. For instance, some peoplehave experienced severe reactions from sulfite-containing medicationsincluding intravenous drugs and inhaled medications, these reactionsincluding flushing, hives, and a drop in lung function. The presentinvention provides the compositions of a “sulfite free” formulation ofepinephrine, which significantly improves the product stability andeliminates the patient's risk of a potential exposure to a severeallergy or asthma reaction from the aforementioned antioxidant ofsulfite related compounds.

In certain embodiments, present invention provides compositions andmethods of using a novel formulation to enhance the physicochemicalstability of epinephrine in an aqueous solution and subsequently extendthe product shelf life. In some embodiments, the invention also providesa safer medication for patients by reducing and/or eliminatingadditives, such as a conventional “sulfite” antioxidant, in theformulation that degrade the epinephrine potency, generates degradationproducts, and potentially causes the subsequent severe asthma and/orallergy reactions. In some embodiments, compositions provided hereinreduce a patient's risk of exposure to unwanted degradation products(e.g., high ESA levels and unnecessary asthma and/or allergy reactionsassociated therewith), a patient's risk of exposure to drastic dosageoverages and/or underages depending on the manufacture date of theproduct, a patient's exposure to unnecessary additives and agents, etc.

In certain embodiments provided herein are pharmaceutically acceptablecompositions comprising epinephrine and any one or more excipients. Inspecific embodiments, compositions provided herein comprise epinephrineand a complexing agent, an antioxidant, a pH buffering agent, achelating agent, a tonicity modifier, or any combination thereof. Inmore specific embodiments, provided herein are compositions comprisingepinephrine and an antioxidant (e.g., cysteine, acetylcysteine,thioglycerol, or any combination thereof). In more specific embodiments,provided herein are compositions comprising epinephrine, a complexingagent (e.g., a cyclodextrin), and an antioxidant (e.g., cysteine,acetylcysteine, thioglycerol, or any combination thereof). In oneembodiment, the pharmaceutical formulation comprises of epinephrine(e.g., formulated as a free base or a pharmaceutically acceptable saltthereof), a complexing agent, an antioxidant, a pH buffering agent, achelating agent and a tonicity modifier in an aqueous based media. Inanother embodiment, the pharmaceutical formulation comprises ofepinephrine (e.g., formulated as a free base or a pharmaceuticallyacceptable salt thereof), an antioxidant, a pH buffering agent, achelating agent and a tonicity modifier in an aqueous based media.

In various embodiments, compositions provided herein are optionallyformulated with any suitable epinephrine, such as the free base,conjugate acid, or a pharmaceutically acceptable salt thereof. Inspecific embodiments, the epinephrine utilized to formulate acomposition provided herein is selected from epinephrine (free base),epinephrine bitartrate, and epinephrine hydrochloride and/or acombination thereof. Generally, compositions described herein ascomprising epinephrine refer to a dissolved epinephrine, whetherdissolved free base, conjugate acid, or a salt thereof. Compositionsprovided herein optionally comprise epinephrine in the free base formand/or in a protonated cation (conjugate acid) or salt form. In someembodiments, the epinephrine is provided in a composition herein and/orformulated into a composition herein in a free base equivalent amount ofabout 0.0001 wt. % to about 5 wt. %. In some instances, concentrationsvary with varying therapeutic treatments and/or administration routes.In specific embodiments, compositions provided herein comprise about0.0001 wt. % to about 1 wt. % epinephrine (e.g., for injectableformulations or topical formulations), about 0.5 wt. % to about 2 wt. %epinephrine (e.g., for ophthalmic drops), about 1 wt. % to about 5 wt. %(e.g., for inhalation formulations). In certain embodiments, theepinephrine is l-epinephrine or (−) epinephrine, such as at aconcentration of about 0.01 wt. % to about 1.0 wt. %.

In some instances, provided herein is the use of cyclodextrin as acomplexing agent to chemically form an inclusion complex withepinephrine. In various embodiments herein, any suitable complexingagent is optionally utilized, such as a native and/or modifiedcyclodextrin derivative. In specific embodiment, a cyclodextrin utilizedin a formulation provided optionally includes, e.g., a α-cyclodextrin,ß-cyclodextrin, γ-cyclodextrin, modified α-cyclodexin, modifiedß-cyclodextin, modified γ-cyclodextrin, and/or a combination thereof. Incertain embodiments, the complexing agent is utilized in a compositionherein in a molar ratio of about 1:10 to about 10:1 of cyclodextrin toepinephrine. In some embodiments, preferred cyclodextrins include, byway of non-limiting example, modified ß-cyclodextins, such ashydroxypropyl β-cyclodextrin (Kleptose® HPB, Kleptose® HP, Trappsol®HPB), sulfobutyl ether β-cyclodextrin (Captisol®), randomly methylatedβ-cyclodextrin (Kleptose® Crysmeb Exp), or a combination thereof. Inspecific embodiments, the compositions comprise and/or are formulatedwith a complexing agent (e.g., cyclodextrin) at a molar ratio of about1:10 to about 2:1, such as about 1:3 to about 2:1 molar ratio, ofcyclodextrin to epinephrine

Cyclodextrins (sometimes called cycloamyloses) are a family of compoundsmade up of sugar molecules bound together in a ring (cyclicoligosaccharides). For example, sulfobutylether β-cyclodextrin (SBEßCD)is a polyanionic beta-cyclodextrin derivative with a sodium sulfonatesalt separated from the lipophilic cavity by a butyl ether spacer group,or sulfobutylether. SBEßCD is not a single chemical species, butcomprised of a multitude of polymeric structures of varying degrees ofsubstitution and positional/regional isomers. SBEßCD is an approvedpharmaceutical ingredient for commercial injectable products.Hydroxypropyl β-cyclodextrin (HPßCD) is the most widely used modifiedß-cyclodextrin with the lipophilic cavity formed by 7 glucose units.HPßCD has the most extensive collection of safety data in the technicalliterature with no adverse reactions reported, and is approved for usefor injectable products and parenteral products.

While not being bound by any theory, examples of association constants(K) of the inclusion complex between epinephrine and SBEßCD in aqueoussolution were reported 488 M⁻¹ and 111 M⁻¹ at pH 3.5 and 5.5,respectively (US 2015/0374832 A1). The K value can be used to determinefree or unbound drug in the complex solution (Rajewski, R. A. andStella, V. J. Pharmaceutical Applications of Cyclodextrins. 2. In VivoDrug Delivery, Journal of Pharmaceutical Sciences, 85(11), 1142-1169,1996) as shown in Equation 1.

where CD is cyclodextrin. The total solubility of epinephrine, a weaklybasic drug in a presence of CD at a low pH range can be described inEquation 2.

S _(Total) =S ₀ +S _(ionic) +S _(Complex)  (2)

where S_(total) is total drug solubility, S₀ is an intrinsic solubilityof drug, S_(ionic) is an ionization solubility of drug, and S_(Complex)is a complex solubility of drug-CD. Equation 2 can also be described inEquation 3.

$\begin{matrix}{S_{total} = {S_{0} + S_{ionic} + \frac{{K\left\lbrack {S_{0} + S_{ionic}} \right\rbrack}\left\lbrack {CD}_{total} \right\rbrack}{{K\left\lbrack {S_{0} + S_{ionic}} \right\rbrack} + 1}}} & (3)\end{matrix}$

where [CD_(total)] is total cyclodextrin added to the solution, and K is1:1 association constant defined by Equation 4.

$\begin{matrix}{K = \frac{\left\lbrack {{Drug} - {CD}_{complex}} \right\rbrack}{\left\lbrack {Drug}_{free} \right\rbrack \left\lbrack {CD}_{free} \right\rbrack}} & (4)\end{matrix}$

Since S_(ionic)>>>S₀, therefore S₀+S_(ionic)≈S_(ionic) and Equation 3can be rewritten by Equation 5.

$\begin{matrix}{S_{total} = {S_{ionic} + \frac{{K\left\lbrack S_{ionic} \right\rbrack}\left\lbrack {CD}_{total} \right\rbrack}{{K\left\lbrack S_{ionic} \right\rbrack} + 1}}} & (5)\end{matrix}$

The fraction of epinephrine in the formulation that would be in complexwith CD at any once instance as determined by Equation 5 is shown inFIG. 1. This data demonstrates that epinephrine is expected to weaklycomplex with SBEßCD at lower pH—where in general, the K values of anydrug and CD complex of 10 to 1×10³ M⁻¹ are common, values of 1×10⁴ M⁻¹are seen occasionally, and values >1×10⁵ M⁻¹ are unusual (Stella V. J.and He Q., Cyclodextrins, Toxicologic Pathology, 36(1), 30-42, 2008).

Generally, this is an important mechanism as the free drug should beimmediately released from the complex after injection in order toprovide its pharmacological effect. In some instances provided herein,the drug is easily released with a minimum dilution of body aqueousfluid like blood upon intramuscular or subcutaneous injection. In oneillustrative example, an injection of 0.3 mL epinephrine (1:1000) in apresence of 1:2 molar ratio of SBEßCD to drug at pH 3.5 (K=488 M⁻¹)would rapidly release 90% and 99% free drug approximately after thedilutions with 3 mL (10×) and 30 mL (100×) body aqueous fluid,respectively as summarized in TABLE 1. A similar exercise may beperformed for a 0.15 mL epinephrine injection of the same aboveformulation for the pediatric patient where the free drug would berapidly released ˜90% and ˜99% after the dilutions with 1.5 mL (10×) and15 mL (100×) body aqueous fluid, respectively (TABLE 1). Thisconservative example assumes fixed volumes, which of course is not thecase in-vivo where the drug is rapidly diffused from the injection site.

TABLE 1 An example of free epinephrine released from 0.15 and 0.3 mLinjection of drug complex (1:1000) containing 1:2 molar ratio of SBEβCDto drug at pH 3.5 (K = 488M⁻¹). Dilution Time (×) Volume (mL) % DrugComplex % Free Drug 1 0.3* 0.15** 26.7 73.3 10 3 1.5 9.5 90.5 100 30 151.3 98.7 1000 300 150 0.1 99.9 *Injection volume for adult patient,**Injection volume for pediatric patient

However, the fraction of non-complex free drug is still susceptible tothe oxidation that could cause the solution discoloration due to a weakassociation constant (K) of epinephrine complex. In some embodiments,compositions further comprise a “non-sulfite” antioxidant, e.g., toprotect the non-complexed free drug in the formulation from theoxidation.

Unexpectedly, a new discovery of antioxidant (e.g., cysteine) level inthe present invention that efficiently inhibit drug oxidation andminimize the cross reaction with drug was found at very lowconcentrations. Indeed, low concentrations of antioxidant (e.g.,cysteine) and low weight ratios of antioxidant to drug are demonstratedherein to provide dramatically improved physiochemical stability(improved potency, reduced degradation products, and improved colorprofile) over time, relative to both compositions lacking antioxidant(e.g., cysteine) and compositions with higher amounts of antioxidant(e.g., cysteine).

In various embodiments, a composition provided herein comprises anysuitable “non-sulfite” antioxidant (including a single antioxidant or acombination of antioxidants). In specific embodiments, “non-sulfite”antioxidants include by way of non-limiting example oxine, boric acid,borate, ascorbic acid, erythorbic acid, malic acid, acetylcysteine(N-acetylcysteine or N-acetyl-L-cysteine), thioglycerol(monothioglycerol or 1-thioglycerol), cysteine (L-cysteine), cysteinehydrochloride, citric acid, polyvinylpyrrolidone and/or any combination(of two or more) thereof. In specific embodiments, antioxidants areincluded in an amount of about 0.001 wt. % to about 2.6 wt. %, e.g.,about 0.001 wt. % to about 0.1, about 0.001 wt. % to about 0.05 wt. %,about 0.005 wt. % to about 0.05 wt. %, about 0.001 wt. % to about 0.02wt. %, or the like. In some embodiments, antioxidant (comprising one ormore antioxidant, such as cysteine, acetylcysteine, thioglycerol, or anycombination (of two or more) thereof) is present in an amount of about0.005 wt. % to about 0.07 wt. %. In specific embodiments, antioxidant ispresent in an amount of about 0.01 wt. % to about 0.07 wt. %. In someembodiments, antioxidant is present in an amount of about 0.005 wt. % toabout 0.05 wt. %. In specific embodiments, antioxidant is present in anamount of about 0.01 wt. % to about 0.05 wt. %. In some embodiments,antioxidant is present in an amount of about 0.015 wt. % to about 0.07wt. %. In specific embodiments, antioxidant is present in an amount ofabout 0.015 wt. % to about 0.05 wt. %. In more specific embodiments, theantioxidant is present in an amount of about 0.02 wt. % to about 0.04wt. %, such as about 0.03 wt. %.

In specific embodiments, a composition herein comprises cysteine (e.g.,as the antioxidant), such as having a concentration of about 0.005 wt. %to about 0.05 wt. % (e.g., about 0.01 wt. % to about 0.04 wt. %). Insome embodiments, a composition herein comprises thioglycerol (e.g., asthe antioxidant), such as having a concentration of about 0.005 wt. % toabout 0.07 wt. %. In some embodiments, a composition herein comprisesacetylcysteine (e.g., as the antioxidant), such as having aconcentration of about 0.005 wt. % to about 0.07 wt. %. In certainembodiments, the antioxidant comprises cysteine and acetylcysteine. Inother embodiments, the antioxidant comprises cysteine and thioglycerol.In still other embodiments, the antioxidant comprises acetylcysteine andthioglycerol.

In further or alternative embodiments, a weight ratio of antioxidant(e.g., cysteine) to drug is less than 1:1, such as about 1:20 to about1:2, e.g., about 1:20 to about 1:5, or the like. In specificembodiments, the weight ratio is about 1:20 to about 1:1, about 1:20 toabout 7:10, about 1:20 to about 1:2, about 1:20 to about 3:10, about1:10 to about 1:1, about 1:10 to about 7:10, about 1:10 to about 1:2,about 1:10 to about 3:10, or the like.

In some embodiments, the weight ratio of antioxidant (e.g., cysteine,acetylcysteine, thioglycerol, or any combination thereof) to drug isabout 7:10 or less (e.g., about 1:2 or less, about 7:20 or less, about3:10 or less, or about 1:5 or less). In some embodiments, the ratio ofantioxidant to drug is about 1:20 or more (e.g., up to an upper limitdescribed above), or about 1:10 or more, about 1:7 or more, about 1:5 ormore, or the like. In certain embodiments, the weight ratio ofantioxidant to drug is about 1:20 to about 7:10 (e.g., about 1:10 toabout 7:10, or about 1:10 to about 5:10). In specific embodiments, theweight ratio of antioxidant-to-epinephrine is about 2:10 to about 4:10(e.g., about 3:10).

In certain embodiments, antioxidants are provided in the composition inan amount as described herein, such as about 0.05 mg/mL to less than 1mg/mL, about 0.05 mg/mL to about 0.7 mg/mL, about 0.05 to about 0.5mg/mL, about 0.05 mg/mL to about 0.35 mg/mL, about 0.05 mg/mL to about0.3 mg/mL, about 0.1 mg/mL to less than 1 mg/mL, about 0.1 mg/mL toabout 0.7 mg/mL, about 0.1 mg/mL to about 0.5 mg/mL, about 0.1 mg/mL toabout 0.35 mg/mL, or about 0.1 mg/mL to about 0.3 mg/mL.

In some instances, pH maintenance is an important contributor to therate of release of active from a complexing agent (e.g., as relating theK value discussed herein). In certain embodiments, a buffering agent isutilized, such as to maintain the pH within the target range. In someembodiments, such as wherein a complexing agent is omitted, thebuffering agent is optionally omitted. The buffering agent formulatedinto a composition herein can be any suitable agent. In specificembodiments, the buffering agent is or comprises, by way of non-limitingexample, acetic acid, acetate (e.g., formulated with sodium acetate,sodium acetate anhydrous), ascorbic acid, ascorbate (e.g., formulatedwith sodium ascorbate), benzoic acid, benzyl benzoic acid, benzylbenzoate, benzoate (e.g., formulated with sodium benzoate),benzenesulfonic acid, citric acid (e.g., formulated with citric acid(anhydrous), citric acid (monohydrate)), citrate (e.g., formulated withsodium citrate, disodium citrate (sesquihydrate), disodium hydrogencitrate, trisodium citrate (anhydrous), or trisodium citrate(dihydrate)), maleic acid, methanesulfonic acid, phosphoric acid,metaphosphoric acid, phosphate (e.g., formulated with potassiumphosphate (monobasic), potassium phosphate (dibasic), sodium phosphate,sodium phosphate (dibasic), sodium phosphate (dibasic, anhydrous),sodium phosphate (dibasic, heptahydrate), sodium phosphate (monobasic),sodium phosphate (monobasic anhydrous), sodium phosphate (monobasic,monohydrate), or sodium phosphate (monobasic, dihydrate)), succinicacid, succinate (e.g., formulated with sodium succinate, or sodiumsuccinate hexahydrate), tartaric acid, tartarate (e.g., formulated withsodium tartarate), and/or a combination thereof. It is to be understoodthat a composition provided herein and formulated with such acomposition may comprise the buffering agent as is, or as a conjugateacid or base thereof (e.g., a composition formulated with citric acidmay comprise citric acid and/or citrate at varying concentrationsdepending on the pH of the composition). In certain embodiments, acomposition provided herein comprises 0.001 wt. % to about 2 wt. %(e.g., about 0.001 wt. % to about 1 wt. %, about 0.001 wt. % to about0.01 wt. %, about 0.001 wt. % to about 0.02 wt. %, about 0.001 wt. % toabout 0.05 wt. %, or the like) buffering agent (e.g., based on combinedweight of conjugate acid and base thereof). In specific embodiments, ofthe composition comprises about 0.005 wt. % to about 0.05 wt. %. Infurther or alternative embodiments, the weight ratio of buffering agent(e.g., citric acid/citrate) to drug is about 1:20 to about 1:2, such asabout 1:20 to about 1:5, about 1:10 to about 1:2, about 1:10 to about1:5, or the like.

In some embodiments, a composition provided herein comprises a chelatingagent, such as to further reduce epinephrine degradation, e.g., due tothe presence of any trace metallic catalyst. Any suitable chelatingagent is optionally utilized. In specific embodiments, the chelatingagent is, by way of non-limiting example, edetate. In variousembodiments, edetate is ethylenediaminetetraacetic acid, or an anion(e.g., −1, −2, −3, or −4 anion), solvate, or salt thereof, such as acompound represented by the formula: (ROOCCH₂)₂NCH₂CH₂N(CH₂COOR)₂,wherein each R is independently H or a negative charge (which negativecharge may be in association with a cationic species, such as Na⁺, Ca⁺,H₃O⁺, or the like). In various embodiments herein, compositionscomprising edetate are formulating using ethylenediaminetetraacetic acidor a pharmaceutically acceptable salt thereof, such as, by way ofnon-limiting example, calcium disodium, edetate disodium, edetatedisodium anhydrous, edetate sodium, edetate disodium dehydrate, edetatetetrasodium, and/or a combination thereof. In some embodiments,chelating agent (e.g., edetate) is utilized in an amount of about 0.001wt % to about 1 wt. %. In specific embodiments, edetate disodium isutilized to formulation a composition herein. In further or alternativeembodiments, chelating agent (e.g., edetate, such as formulated withedetate disodium) is utilized in an amount of about 0.001 wt. % to about0.05 wt. % (e.g., about 0.005 wt. % to about 0.05 wt. %, about 0.005 wt.% to about 0.01 wt. %, or the like). In some embodiments, the weightratio of chelating agent (e.g. edetate—e.g., using edetate disodium informulating) to epinephrine is about 1:20 to about 1:2.

In some embodiments, water suitable for injection (WFI) is utilized asan aqueous diluent. In some instances, the pH of WFI is adjusted toeffectively enhance the physicochemical stability of epinephrine complexformulation (e.g., using hydrochloric acid and/or sodium hydroxide) to aspecific range of pH 2-5 (e.g., about pH 2.5, about pH 3.5, about pH 2.5to about pH 3.5, or the like).

In some embodiments, a tonicity modifier is utilized to adjust thesolution osmolality within a body physiological range. Any suitabletonicity modifier is optionally utilized, such as, by way ofnon-limiting example, sodium chloride and/or dextrose or a combinationthereof. In specific embodiments, sodium chloride is utilized(dissolved/disassociated sodium chloride being present in a compositionherein). In specific embodiments, a tonicity modifier is used to providethe solution osmolality within a range of about 200-400 mOsm/kg.

In another embodiment, epinephrine complex and non-complex formulationsis used in a conjunction with an administrative device. Any suitabledevice is utilized. In specific embodiments, the device is, by way ofnon-limiting example, a pre-filled syringe or cartridge with or withoutthe auto injector for both manual and auto injections. In someinstances, such devices are calibrated and/or configured to preciselyand accurately deliver effective amount of epinephrine medication.

In another embodiment, epinephrine complex and non-complex formulationscan be used for treating anaphylactic shock by administratingepinephrine formulation to patients via intramuscular injection orsubcutaneous injection or intravenous injection.

It is to be understood that any reference to a composition comprising anassociate compound described herein (e.g., a salt or an acid) includes acomposition comprising disassociated and/or solvated forms of thatcompound (e.g., ions of a salt and/or conjugate base of an acid).

The following non-limiting examples are provided to further explain andillustrate the invention.

EXAMPLES

Pharmaceutical formulations are prepared by mixing cyclodextrin,edetate, citric acid, cysteine, and sodium chloride into a pH 2.0 WFIprior to adding and mixing epinephrine. Adjust formulation pH to thetarget pH using HCl and/or NaOH solutions. Adjust the final volume usinga target pH WFI. Examples 1-10 are prepared using this procedure.

Example 1

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0 SBEβCD6.0 Cysteine 5.0 Citric Acid 5.0 Edetate 2.0 Sodium Chloride 7.8 HCland/or NaOH (pH 2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 2

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0 SBEβCD6.0 Cysteine 5.0 Citric Acid 5.0 Edetate 2.0 Sodium Chloride 7.8 HCland/or NaOH (pH 3.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 3

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0 HPβCD4.0 Cysteine 5.0 Citric Acid 5.0 Edetate 2.0 Sodium Chloride 7.8 HCland/or NaOH (pH 2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 4

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0 HPβCD4.0 Cysteine 5.0 Citric Acid 5.0 Edetate 2.0 Sodium Chloride 7.8 HCland/or NaOH (pH 3.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 5

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0 SBEβCD6.0 Cysteine 2.0 Citric Acid 2.0 Edetate 0.2 Sodium Chloride 7.8 HCland/or NaOH (pH 3.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 6

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0 HPβCD4.0 Cysteine 2.0 Citric Acid 2.0 Edetate 0.2 Sodium Chloride 7.8 HCland/or NaOH (pH 3.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 7

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0 SBEβCD6.0 Cysteine 1.0 Citric Acid 1.0 Edetate 0.1 Sodium Chloride 7.8 HCland/or NaOH (pH 2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 8

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0 HPβCD4.0 Cysteine 1.0 Citric Acid 1.0 Edetate 0.1 Sodium Chloride 7.8 HCland/or NaOH (pH 2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 9

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0 SBEβCD6.0 Cysteine 0.1 Citric Acid 0.1 Edetate 0.1 Sodium Chloride 7.8 HCland/or NaOH (pH 2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 10

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0 HPβCD4.0 Cysteine 0.1 Citric Acid 0.1 Edetate 0.1 Sodium Chloride 7.8 HCland/or NaOH (pH 2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

The method of preparing non-complex formulations and using anantioxidant in Examples 11-15 is carried out by mixing edetate, citricacid, cysteine, and sodium chloride into a pH 2.0 WFI prior to addingand mixing epinephrine. Adjust formulation pH to the target pH using HCland/or NaOH solutions. Adjust the final volume using a target pH WFI.

Example 11

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0 Cysteine0.1 Citric Acid 0.1 Edetate 0.1 Sodium Chloride 7.8 HCl and/or NaOH (pH2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 12

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0 Cysteine0.3 Citric Acid 0.1 Edetate 0.1 Sodium Chloride 7.8 HCl and/or NaOH (pH2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 13

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0 Cysteine0.5 Citric Acid 0.1 Edetate 0.1 Sodium Chloride 7.8 HCl and/or NaOH (pH2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 14

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0 Cysteine0.7 Citric Acid 0.1 Edetate 0.1 Sodium Chloride 7.8 HCl and/or NaOH (pH2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 15

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0 Cysteine1.0 Citric Acid 0.1 Edetate 0.1 Sodium Chloride 7.8 HCl and/or NaOH (pH2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

The method of preparing non-complex formulation and using an antioxidantin Examples 16-20 is carried out by mixing edetate, citric acid,thioglycerol, and sodium chloride into a pH 2.0 WFI prior to adding andmixing epinephrine. Adjust formulation pH to the target pH using HCland/or NaOH solutions. Adjust the final volume using a target pH WFI.

Example 16

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0Thioglycerol 0.1 Citric Acid 0.1 Edetate 0.1 Sodium Chloride 7.8 HCland/or NaOH (pH 2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 17

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0Thioglycerol 0.3 Citric Acid 0.1 Edetate 0.1 Sodium Chloride 7.8 HCland/or NaOH (pH 2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 18

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0Thioglycerol 0.5 Citric Acid 0.1 Edetate 0.1 Sodium Chloride 7.8 HCland/or NaOH (pH 2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 19

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0Thioglycerol 0.7 Citric Acid 0.1 Edetate 0.1 Sodium Chloride 7.8 HCland/or NaOH (pH 2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 20

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0Thioglycerol 1.0 Citric Acid 0.1 Edetate 0.1 Sodium Chloride 7.8 HCland/or NaOH (pH 2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

The method of preparing non-complex formulations and using anantioxidant in Examples 21-25 is carried out by mixing edetate, citricacid, acetylcysteine, and sodium chloride into a pH 2.0 WFI prior toadding and mixing epinephrine. Adjust formulation pH to the target pHusing HCl and/or NaOH solutions. Adjust the final volume using a targetpH WFI.

Example 21

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0Acetylcysteine 0.1 Citric Acid 0.1 Edetate 0.1 Sodium Chloride 7.8 HCland/or NaOH (pH 2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 22

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0Acetylcysteine 0.3 Citric Acid 0.1 Edetate 0.1 Sodium Chloride 7.8 HCland/or NaOH (pH 2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 23

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0Acetylcysteine 0.5 Citric Acid 0.1 Edetate 0.1 Sodium Chloride 7.8 HCland/or NaOH (pH 2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 24

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0Acetylcysteine 0.7 Citric Acid 0.1 Edetate 0.1 Sodium Chloride 7.8 HCland/or NaOH (pH 2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 25

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0Acetylcysteine 1.0 Citric Acid 0.1 Edetate 0.1 Sodium Chloride 7.8 HCland/or NaOH (pH 2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

The method of preparing non-complex formulations and using mixedantioxidants in Examples 26-28 is carried out by mixing edetate, citricacid, antioxidants (i.e. cysteine, thioglycerol and acetylcysteine) andsodium chloride into a pH 2.0 WFI prior to adding and mixingepinephrine. Adjust formulation pH to the target pH using HCl and/orNaOH solutions. Adjust the final volume using a target pH WFI.

Example 26

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0 Cysteine0.1 Thioglycerol 0.1 Citric Acid 0.1 Edetate 0.1 Sodium Chloride 7.8 HCland/or NaOH (pH 2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 27

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0 Cysteine0.1 Acetylcysteine 0.1 Citric Acid 0.1 Edetate 0.1 Sodium Chloride 7.8HCl and/or NaOH (pH 2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 28

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0Thioglycerol 0.1 Acetylcysteine 0.1 Citric Acid 0.1 Edetate 0.1 SodiumChloride 7.8 HCl and/or NaOH (pH 2.5 ± 0.1) q.s. Water for Injection(WFI) q.s. Water for Injection (WFI) q.s.

The method of preparing non-complex pediatric formulations in Examples29-32 is carried out by mixing edetate, citric acid, antioxidants (i.e.cysteine, thioglycerol and acetylcysteine) and sodium chloride into a pH2.0 WFI prior to adding and mixing epinephrine. Adjust formulation pH tothe target pH using HCl and/or NaOH solutions. Adjust the final volumeusing a target pH WFI.

Example 29

Ingredient Concentration (mg/mL) Epinephrine (as free base) 0.5 Cysteine0.1 Citric Acid 0.1 Edetate 0.1 Sodium Chloride 7.8 HCl and/or NaOH (pH2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 30

Ingredient Concentration (mg/mL) Epinephrine (as free base) 0.5 Cysteine0.1 Thioglycerol 0.1 Citric Acid 0.1 Edetate 0.1 Sodium Chloride 7.8 HCland/or NaOH (pH 2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 31

Ingredient Concentration (mg/mL) Epinephrine (as free base) 0.5 Cysteine0.1 Acetylcysteine 0.1 Citric Acid 0.1 Edetate 0.1 Sodium Chloride 7.8HCl and/or NaOH (pH 2.5 ± 0.1) q.s. Water for Injection (WFI) q.s.

Example 32

Ingredient Concentration (mg/mL) Epinephrine (as free base) 0.5Thioglycerol 0.1 Acetylcysteine 0.1 Citric Acid 0.1 Edetate 0.1 SodiumChloride 7.8 HCl and/or NaOH (pH 2.5 ± 0.1) q.s. Water for Injection(WFI) q.s.

Example 33

The method of preparing a typical commercial “sulfite” formulation inExamples 33 was carried out by mixing sodium chloride and sodiumbisulfite into a pH 2.2 WFI prior to adding and mixing epinephrine.Adjust formulation pH to the target pH using HCl and/or NaOH solutions.Adjust the final volume using a target pH WFI.

Ingredient Concentration (mg/mL) Epinephrine (as free base) 1.0 SodiumBisulfite 1.5 Sodium Chloride 8.5 HCl and/or NaOH (pH 3.5 ± 0.1) q.s.Water for Injection (WFI) q.s.

All epinephrine formulation candidates were tested for drug potency, pHand appearance of coloration and precipitation. Selected samples werealso tested for drug chirality. The potency and chirality of drug wereanalyzed using HPLC methods. The degree of coloration was visuallyinspected and analytically measured their optical densities using aUV/VIS spectrophotometer at the maximum absorption wavelength (λ_(max))at 485 nm. Iodine solution (0.0005 N) in water was used as a referencestandard to confirm the instrument read-out consistency.

Surprisingly, as illustrated in TABLES 2-4, after 1 month storage at 50°C., substantial drug degradations were observed in samples havingcysteine levels of 0.1 wt. % to 0.5 wt. % or 1:1 to 5:1 weight ratio ofcysteine-to-drug (compositions of Examples 1-8).

At 5:1 weight ratio of cysteine-to-drug, epinephrine in both SBEßCD andHPßCD formulations was rapidly degraded in the same fashion to be ˜67%(Examples 1 and 3) and ˜86-90% (Examples 2 and 4) at pHs 2.5 and 3.5,respectively as shown in TABLE 2. The appearances of precipitation andslight discoloration were similarly observed in both complexformulations at pH 2.5 and 3.5, respectively (TABLE 2).

TABLE 2 Stabilities of epinephrine complex formulations containing about0.5 wt. % antioxidant (cysteine) (5:1 weight ratio of cysteine-to-drug)after 1 month storage at 50° C. Potency Example CD (%) pH AppearanceO.D. 1 SBEβCD 66.5 2.6 Colorless & 0.0039 precipitation 2 SBEβCD 86.03.5 Slightly light tan 0.0086 3 HPβCD 67.4 2.6 Colorless & 0.0057precipitation 4 HPβCD 89.5 3.6 Slightly light tan 0.0086 NA 0.0005N NANA Slightly brownish 0.1290 Iodine ND = Not detected; NA = NotApplicable; O.D. = Optical density (Absorbance at λmax = 485 nm)

At 2:1 weight ratio of cysteine-to-drug (Examples 5 and 6), epinephrinedegradations in both complex formulations at pH 3.5 were found to be˜87-93% and comparable to that (˜86-90%) at 5:1 weight ratio (Examples 2and 4) and same pH condition as shown in TABLE 3. The appearances ofboth formulations were “clear, colorless & no particulates”.

TABLE 3 Stabilities of epinephrine complex formulations containing about0.2 wt. % antioxidant (cysteine) (2:1 weight ratio of cysteine-to-drug)after 1 month storage at 50° C Example CD Potency (%) pH Appearance O.D.5 SBEβCD 87.1 3.4 Clear, colorless & 0.0142 no particulates 6 HPβCD 92.93.5 Clear, colorless & 0.0024 no particulates NA 0.0005N NA NA Slightlybrownish 0.1206 Iodine ND = Not detected; NA = Not Applicable; O.D. =Optical density (Absorbance at λmax = 485 nm)

At 1:1 weight ratio of cysteine-to-drug (Examples 7 and 8), epinephrinedegradations in both complex formulations at pH 2.5 were found to be˜85-92% with some improvements over that (˜67%) at 5:1 weight ratio(Examples 1 and 3) and same pH condition as shown in TABLE 4. Theappearances of both formulations were “clear, colorless & noparticulates”.

TABLE 4 Stabilities of epinephrine complex formulations containing about0.1 wt. % antioxidant (cysteine) (1:1 weight ratio of cysteine-to-drug)at after 1 month storage at 50° C. Example CD Potency (%) pH AppearanceO.D. 7 SBEβCD 85.3 2.5 Clear, colorless & 0.0146 no particulates 8 HPβCD91.7 2.5 Clear, colorless & 0.0018 no particulates NA 0.0005N NA NASlightly brownish 0.1206 Iodine ND = Not detected; NA = Not Applicable;O.D. = Optical density (Absorbance at λmax = 485 nm)

As demonstrated in FIG. 2, an example of HPLC chromatogram of relateddegradants were observed ˜11.2% (peak area) in an epinephrine solutioncontaining 0.1 wt. % cysteine or 1:1 weight ratio of cysteine-to-drug atpH 2.5 (Example 15) after 1 month storage at 50° C.

Unexpectedly, at lower antioxidant (cysteine) levels (e.g., below 0.1wt. % or lower than 1:1 weight ratio of antioxidant (cysteine)-to-drug),degradation of epinephrine actually decreased. For instance at 0.01 wt.% cysteine or 1:10 weight ratio of cysteine-to-drug, an excellentimprovement of physicochemical stability of epinephrine in both complexformulations (Examples 9 and 10) were discovered to remain ˜100% drugpotency after 1 month storage at 50° C. as shown in TABLE 5.

A typical commercial “sulfite” formulation (Example 33) was also studiedand compared as a benchmark for physicochemical improvements of “sulfitefree” formulations. After 1 month storage at 50° C., drug potency incommercial formulation rapidly degraded to be ˜74% compared to ˜100% ofthat in both SBEßCD and HPßCD formulations. The degradation products inthe commercial formulation mainly epinephrine sulfonic acid (ESA) wasfound >37% compared to “not detected” levels in both formulations. Theappearances of both complex formulations were observed to be “clear,colorless & no particulates” compared to a discoloration of “slightlybrownish-tan” of that from the commercial one. The testing results aresummarized and compared in TABLE 5.

Examples of HPLC chromatograms demonstrating novel physicochemicalstability improvements in SBEßCD and HPßCD formulations withinsignificant degradant levels in the present invention are illustratedin FIGS. 3 and 4, respectively.

TABLE 5 Stabilities of epinephrine complex formulations containing about0.01 wt. % antioxidant (cysteine) (1:10 weight ratio ofcysteine-to-drug) and a commercial formulation after 1 month storage at50° C. Potency ESA Example CD (%) (%) pH Appearance O.D.  9 SBEβCD 100.1ND 2.5 Clear, colorless 0.0059 & no particulates 10 HPβCD 99.5 ND 2.5Clear, colorless 0.0060 & no particulates 33 None 74.0 >37 3.4 Slightlybrownish- N/A (Commercial tan Formulation) 0.0005N None NA NA NASlightly brownish 0.1354 Iodine ND = Not detected; NA = Not Applicable;O.D. = Optical density (Absorbance at λmax = 485 nm)

The physicochemical improvement of epinephrine was also discovered in anon-complex formulation containing low levels of cysteine (0.01 and 0.03wt. % or 1:10 and 3:10 weight ratio of cysteine-to-drug in Example 11and 12, respectively) to be ˜99% drug potency compared to ˜90-97% athigher levels (0.05, 0.07 and 0.1 wt. % or 5:10, 7:10 and 1:1 weightratio of cysteine-to-drug in Example 13, 14 and 15, respectively) after1 month storage at 50° C. as shown in TABLE 6.

TABLE 6 Stabilities of non-complex epinephrine formulations at differentantioxidant levels of cysteine after 1 month storage at 50° C. DegradantCysteine: Potency (% peak Example Drug (%) area) pH Appearance O.D. 111:10 98.7 ND 2.5 Clear, colorless & 0.0028 no particulates 12 3:10 99.2ND 2.5 Clear, colorless & 0.0019 no particulates 13 5:10 97.4 2.6 2.5Clear, colorless & 0.0025 no particulates 14 7:10 95.0 5.0 2.5 Clear,colorless & 0.0029 no particulates 15 1:1  89.8 11.2 2.5 Clear,colorless & 0.0038 no particulates 0.0005N N/A NA NA NA Slightlybrownish 0.1354 Iodine ND = Not detected; NA = Not Applicable; O.D. =Optical density (Absorbance at λmax = 485 nm)

The physicochemical improvement of epinephrine was also discovered in anon-complex formulation containing low levels of thioglycerol (0.0,0.03, 0.05 and 0.07 wt. % or 1:10, 3:10, 5:10 and 7:10 weight ratio ofthioglycerol in Examples 16, 17, 18, 19 and 20, respectively) to be ˜99%drug potency compared to ˜97% at a higher level (0.1 wt. % or 1:1 weightratio of thioglycerol in Example 20) after 1 month storage at 50° C. asshown in TABLE 7.

TABLE 7 Stabilities of non-complex epinephrine formulations at differentantioxidant levels of thioglycerol after 1 month storage at 50° C. Thio-Degradant glycerol: Potency (% peak Example Drug (%) area) pH AppearanceO.D. 16 1:10 99.2 ND 2.5 Clear, colorless 0.0018 & no particulates 173:10 99.1 ND 2.5 Clear, colorless 0.0023 & no particulates 18 5:10 98.9ND 2.5 Clear, colorless 0.0022 & no particulates 19 7:10 99.2 ND 2.5Clear, colorless 0.0019 & no particulates 20 1:1  97.3 2.7 2.5 Clear,colorless 0.0025 & no particulates 0.0005N N/A NA NA NA Slightly 0.1354Iodine brownish ND = Not detected; NA = Not Applicable; O.D. = Opticaldensity (Absorbance at λmax = 485 nm)

The physicochemical improvement of epinephrine was also discovered in anon-complex formulation containing low levels of acetylcysteine (0.0,0.03, 0.05 and 0.07 wt. % or 1:10, 3:10, 5:10 and 7:10 weight ratio ofacetylcysteine in Examples 21, 22, 23 and 24, respectively) to be ˜99%drug potency compared to ˜97% at a higher level (0.1 wt. % or 1:1 weightratio of acetylcysteine in Example 25) after 1 month storage at 50° C.as shown in TABLE 8.

TABLE 8 Stabilities of non-complex epinephrine formulations at differentantioxidant levels of acetylcysteine after 1 month storage at 50° C.Acetyl- Degradant cysteine: Potency (% peak Example Drug (%) area) pHAppearance O.D. 21 1:10 99.9 ND 2.5 Clear, colorless 0.0022 & noparticulates 22 3:10 97.6 ND 2.5 Clear, colorless 0.0019 & noparticulates 23 5:10 100.4 ND 2.5 Clear, colorless 0.0028 & noparticulates 24 7:10 98.8 ND 2.5 Clear, colorless 0.0015 & noparticulates 25 1:1  97.0 3.0 2.5 Clear, colorless 0.0023 & noparticulates 0.0005N N/A NA NA NA Slightly 0.1354 Iodine brownish ND =Not detected; NA = Not Applicable; O.D. = Optical density (Absorbance atλmax = 485 nm)

The physicochemical improvement of epinephrine was also discovered in anon-complex formulation containing low levels of mixed antioxidants at0.01 wt. % or 1:10 weight ratio of each antioxidant to drug. Theformulations of mixed antioxidants of cysteine/acetylcysteine,cystenine/thioglycerol and thioglycerol/acetylcysteine are describedExamples 26, 27 and 28, respectively. All combinations of mixedantioxidants demonstrated the drug potency to be ˜99-100% after 1 monthstorage at 50° C. as shown in TABLE 9.

TABLE 9 Stabilities of non-complex epinephrine formulations using mixedantioxidants at 1:10 ratio of antioxidant to drug or 0.01 wt. % after 1month storage at 50° C. Degradant Potency (% peak Example Antioxidants(%) area) pH Appearance O.D. 26 Cysteine/ 99.5 ND 2.5 Clear, color-0.0022 Acetylcysteine less & no particulates 27 Cysteine/ 99.5 ND 2.5Clear, color- 0.0019 Thioglycerol less & no particulates 28Thioglycerol/ 98.6 ND 2.5 Clear, color- 0.0028 Acetylcysteine less & noparticulates 0.0005N N/A NA NA NA Slightly 0.1354 Iodine brownish ND =Not detected; NA = Not Applicable; O.D. = Optical density (Absorbance atλmax = 485 nm)

The pediatric formulations of epinephrine injection (1:2000) foranaphylaxis treatment were also explored to enhance theirphysicochemical stabilities and extend the product shelf lives. Thenon-complex formulations were investigated using a single antioxidant inExample 29 or mixed antioxidants in Examples 30-32. The physicochemicalstability improvements were discover in all formulations with the drugpotency greater than 99% as shown in Table 10.

TABLE 10 Stabilities of non-complex pediatric epinephrine formulations(1:2000) using single or mixed antioxidants at 1:10 ratio of antioxidantto drug or 0.01 wt. % after 1 month storage at 50° C. Degradant Anti-Potency (% peak Example oxidant(s) (%) area) pH Appearance O.D. 29Cysteine 100.0 ND 2.5 Clear, color- 0.0020 less & no particulates 30Cysteine/ 99.2 ND 2.5 Clear, color- 0.0017 Acetylcysteine less & noparticulates 31 Cysteine/ 99.7 ND 2.5 Clear, color- 0.0025 Thioglycerolless & no particulates 32 Thioglycerol/ 99.7 ND 2.5 Clear, color- 0.0013Acetylcysteine less & no particulates 0.0005N N/A NA NA NA Slightly0.1354 Iodine brownish ND = Not detected; NA = Not Applicable; O.D. =Optical density (Absorbance at λmax = 485 nm)

The physicochemical stabilities of two complex formulations (Examples 9and 10) were also evaluated and compared with a commercial product at alonger accelerated stability condition at 40° C./75% RH for six monthsunder a guidance from ICH (The International Council for Harmonizationof Technical Requirements for Pharmaceuticals for Human Use).

After six months under an ICH storage condition at 40° C./75% RH,epinephrine in the commercial formulation was rapidly degraded to be˜79% compared to >95% of certain exemplified formulations in the presentinvention. The degradation products in the commercial formulation mainlyepinephrine sulfonic acid (ESA) was found ˜32% compared to “notdetected” levels in both formulations of the present invention. Thetesting results are summarized and presented in TABLE 11.

TABLE 11 Physicochemical stabilities of epinephrine complex formulationscontaining 0.01 wt. % antioxidant (cysteine) (1:10 weight ratio ofcysteine-to-drug) and a typical commercial “sulfite” formulation after 6month storage at 40° C./75% RH Potency ESA Example CD (%) (%) pHAppearance  9 SBEβCD >95 ND 2.6 Clear, colorless & no particulates 10HPβCD >95 ND 2.6 Clear, colorless & no particulates 33 None 79.1 31.83.4 Clear, colorless & (Commercial no particulates Formulation) ND = Notdetected

After twelve (12) months under an ICH storage condition at 25° C./60%RH, epinephrine in all commercial formulations including EpiPen,Adrenaclick and Auvi-Q were similarly degraded to be ˜91-93% from theirinitial values at 110-112% overages compared to ˜100% from that at 100%target of certain exemplified formulations in the present invention. Thedegradation products in the commercial formulations mainly epinephrinesulfonic acid (ESA) was found ˜9-11% compared to “not detected” levelsin both formulations of the present invention. The testing results aresummarized and presented in TABLE 8.

TABLE 8 Physicochemical stabilities of epinephrine complex formulationscontaining about 0.01 wt. % antioxidant (cysteine) (1:10 weight ratio ofcysteine-to-drug) and the other commercial products after 12 monthstorage at 25° C./60% RH Potency ESA Example CD (%) (%) pH Appearance 9SBEβCD ~100 ND 2.5 Clear, colorless & no particulates 10 HPβCD ~100 ND2.5 Clear, colorless & no particulates EpiPen None ~91-93 ~9-11 2.5-4.5Clear, colorless & Adrenaclick no particulates Auvi-Q ND = Not detected

In addition, after 3.5 months under ICH storage condition at 40° C./75%RH, the chirality of epinephrine racemization was also found <3%d-epinephrine in both complex formulations (Examples 9 & 10) as shown inTABLE 9. Examples of HPLC chromatograms demonstrating drug racemizationin both SBEßCD and HPßCD formulations are shown in FIGS. 8 and 9,respectively.

TABLE 9 Chirality of epinephrine complex formulations at pH 2.5 after3.5 month storage at 40° C./75% RH d-Epinephrine (%) Example CD Initial3.5 Months Appearance 9 SBEβCD 1.4 2.9 Clear, colorless & noparticulates 10 HPβCD 1.4 1.7 Clear, colorless & no particulates

Example 34

Epinephrine formulations as described herein are indicated in thetreatment (e.g., emergency treatment) of allergic reactions (e.g., TypeI) including, for example, anaphylaxis to stinging insects (e.g., orderHymenoptera, which include bees, wasps, hornets, yellow jackets and fireants) and biting insects (e.g., triatoma, mosquitoes), allergenimmunotherapy, foods, drugs, diagnostic testing substances (e.g.,radiocontrast media) and other allergens, as well as idiopathicanaphylaxis or exercise-induced anaphylaxis. Epinephrine formulations inthe present invention are intended for immediate administration inpatients who are determined to be at increased risk for anaphylaxis,including individuals with a history of anaphylactic reactions.

Anaphylactic reactions may occur within minutes after exposure andconsist of flushing, apprehension, syncope, tachycardia, thready orunobtainable pulse associated with a fall in blood pressure,convulsions, vomiting, diarrhea and abdominal cramps, involuntaryvoiding, wheezing, dyspnea due to laryngeal spasm, pruritus, rashes,urticaria or angioedema. Epinephrine formulations in the presentinvention are intended for immediate administration as emergencysupportive therapy only and are not a substitute for immediate medicalcare.

Selection of the appropriate dosage strength of the epinephrineformulations (e.g., a formulation of any one of Examples 9-31) isdetermined according to patient body weight. Patients greater than orequal to 30 kg (approximately 66 pounds or more) are required 0.3 mgdose or 0.3 mL epinephrine formulation (1:1000). Patients of 15 to 30 kg(33 pounds to 66 pounds) are required 0.15 mg dose or 0.15 mLepinephrine formulation (1:1000) or alternatively 0.3 mL epinephrineformulation (1:2000). The epinephrine formulation is intramuscularly orsubcutaneously injected into the anterolateral aspect of the thigh,through clothing if necessary.

The prescriber should carefully assess each patient to determine themost appropriate dose of epinephrine, recognizing the life-threateningnature of the reactions for which this drug is indicated. With severepersistent anaphylaxis, repeat injections may be necessary. More thantwo sequential doses of epinephrine should only be administered underdirect medical supervision.

Epinephrine formulation should only be injected into the anterolateralaspect of the thigh. Do not inject intravenously. Rapidly actingvasodilators can counteract the marked pressor effects of epinephrine ifthere is such inadvertent administration. Do not inject into digits,hands or feet. Since epinephrine is a strong vasoconstrictor wheninjected into the digits, hands, or feet, treatment should be directedat vasodilatation if there is such an accidental injection to theseareas. Do not inject into buttock. If there is an accidental injectioninto these areas, advise the patient to inform the healthcare providerof the accidental injection when he/she goes to the nearest emergencyroom for further treatment of anaphylaxis.

Epinephrine should be administered with caution to patients who haveheart disease, including patients with cardiac arrhythmias, coronaryartery or organic heart disease, or hypertension. In such patients, orin patients who are on drugs that may sensitize the heart toarrhythmias, epinephrine may precipitate or aggravate angina pectoris aswell as produce ventricular arrhythmias. Epinephrine should beadministered with caution to patients with hyperthyroidism, diabetes,elderly individuals, and pregnant women. Patients with Parkinson'sdisease may notice a temporary worsening of symptoms.

Unlike all commercial products currently available on the market,certain epinephrine formulations in the present invention are a “sulfitefree” formulation and safe for the sulfite-sensitive patient.

1. A pharmaceutical composition comprising: epinephrine; one or moreantioxidant, the antioxidant being present in the composition in anamount of about 0.005 wt. % to about 0.07 wt. %; and an aqueous medium;wherein the pharmaceutical composition has a pH of at least 3.5.
 2. Apharmaceutical composition comprising: epinephrine; and cysteine, thecysteine being present in the composition in a cysteine-to-epinephrineweight ratio of about 7:10 or less.
 3. The pharmaceutical composition ofclaim 1, wherein the one or more antioxidant comprises cysteine,acetylcysteine, thioglycerol, or any combination thereof.
 4. Thepharmaceutical composition of claim 3, wherein the one or moreantioxidant is cysteine.
 5. (canceled)
 6. (canceled)
 7. (canceled) 8.(canceled)
 9. (canceled)
 10. The pharmaceutical composition of claim 1,wherein the antioxidant is present in a concentration of about 0.005 wt.% to about 0.035 wt. %.
 11. The pharmaceutical composition of claim 4,wherein the antioxidant is present in a concentration of about 0.005 wt.% to about 0.03 wt. %.
 12. (canceled)
 13. (canceled)
 14. (canceled) 15.(canceled)
 16. The pharmaceutical composition of claim 1, wherein (i)after six months of storage at 40±2° C. and 75±5% relative humidity(RH), (i) the composition comprises at least 90 wt. % of the epinephrinein the composition prior to storage; (ii) after 12 months of storage at25±2° C. and 60±5% relative humidity (RH) the composition comprises atleast 90 wt. % of the epinephrine in the composition prior to storage;and (iii) after 12 months of storage at 25±2° C. and 60±5% relativehumidity (RH) the composition is substantially colorless.
 17. (canceled)18. The pharmaceutical composition of claim 11, wherein after at least 1year of storage at 25° C./60% RH, less than 10% of the epinephrine isd-epinephrine.
 19. (canceled)
 20. (canceled)
 21. (canceled) 22.(canceled)
 23. The pharmaceutical composition of claim 1, wherein theepinephrine is present in the composition in an amount of about 0.01 wt.% to about 1 wt. % on a free base basis.
 24. The pharmaceuticalcomposition of claim 11, wherein the epinephrine is present in thecomposition in an amount of about 0.05 wt. % to about 0.15 wt. % on afree base basis.
 25. (canceled)
 26. The pharmaceutical composition ofclaim 1, wherein the complexing agent is one or more cyclodextrin. 27.(canceled)
 28. The pharmaceutical composition of claim 26, wherein thecyclodextrin is present in the composition in a molar ratio ofcyclodextrin-to-epinephrine of about 1:10 to about 10:1.
 29. Thepharmaceutical composition of claim 28, wherein the cyclodextrin ispresent in the composition in a molar ratio ofcyclodextrin-to-epinephrine of about 1:3 to about 2:1.
 30. Thepharmaceutical composition of claim 1, wherein the antioxidant ispresent in the composition in a weight ratio of antioxidant toepinephrine of about 7:10 or less.
 31. (canceled)
 32. (canceled) 33.(canceled)
 34. The pharmaceutical composition of claim 1, furthercomprising one or more pH buffering agent, the combined weight of pHbuffering agent(s) constituting about 0.01 wt. % or less of thecomposition.
 35. (canceled)
 36. The pharmaceutical composition of claim1, further comprising a edetate, the edetate being present in thecomposition in an amount of about 0.01 wt. % or less.
 37. (canceled) 38.The pharmaceutical composition of claim 1, wherein a tonicity modifieris present in the composition in an amount suitable to provide asolution osmolality in the range of about 200 mOsm/kg to about 400mOsm/kg.
 39. The pharmaceutical composition of claim 1, wherein thecomposition is an aqueous solution having a pH of about 3.5 to about6.5.
 40. (canceled)
 41. (canceled)
 42. (canceled)
 43. A method fortreating anaphylaxis, anaphylactic shock, or the symptoms thereof, themethod comprising administering to an individual in need thereof atherapeutically effective amount of a composition of claim
 1. 44.(canceled)
 45. (canceled)
 46. (canceled)
 47. (canceled)
 48. (canceled)49. A method of inhibiting the systemic distribution of locallyadministered anesthetic by administering the anesthetic concomitantlywith (i) epinephrine and (ii) cysteine to an individual in need of alocal anesthetic, wherein the epinephrine and antioxidant areadministered in an antioxidant-to-epinephrine ratio of less than 1:2,wherein the epinephrine is formulated at a pH of at least 3.5. 50.(canceled)
 51. (canceled)